Dell POWEREDGE R720 - Manual (Page 13)

– Note that the attribute ID# are listed in decimal and not in Hex with the Attribute_NAME associated with
Hard Drives.
Figure 8. Reading the SMART drive wear attributes
The table below translates the data from smartctl to the Intel-supported SMART Attributes.
Table 1. Converting SMART attribute values
Attribute Decimal ID Hex ID Raw Value
Host Writes Count 225 E1h 477242
Timed Workload Media
Wear Indicator 226 E2h 635
Timed Workload Host Read/
Write Ratio 227 E3h 0
Workload Timer 228 E4h 1367
Calculating Estimated Drive Wear
From the data collected using smartctl, and the translated values, you can then calculate the drive wear rate based on
the given workload. Using this example:
• Timed Workload Media Wear (E2h) has a raw value of 635. Therefore, the percentage wear rate = 635/1024 =
0.620%
• Timed Workload Host Read/Write Ratio (E3h) has a normalized value of 0, indicating that 0% of the operations
were reads. This corresponds with the 100% random write workload set in Iometer.
• Workload Timer (E4h) has a raw value of 1367. Therefore the workload ran for 1367 minutes or 22.783 hours.
Given these values, the media wear percentage rate for this workload can then be calculated:
13